CN205558891U - Binary formula oil well three -phase automatic measurement ware - Google Patents

Abstract

The utility model provides a binary formula oil well three -phase automatic measurement ware, includes the first jar body, the second jar body, two electric T -shaped valve and automatic control, be provided with a differential pressure transmitter and the 3rd differential pressure transmitter on the first jar of body, be provided with the 2nd differential pressure transmitter and fourth differential pressure transmitter on the second jar body, the 3rd differential pressure transmitter and fourth differential pressure transmitter set up respectively between a differential pressure transmitter and the 2nd differential pressure transmitter, two jar body sizes are identical, and the import and the export of two jar bodies are connected with two electric T -shaped valve respectively, and the upper portion of two jar bodies is connected with the communicating pipe that is used for gaseous exchange, pressure transmitter and temperature transmitter are equipped with to the top of the jar body, each electronic part ware all is connected with the controller. This counter simple structure only can measure out profit proportion, profit output and gas production through four differential pressure transmitter's data combination, has realized that the oil well flow carries out in succession real -time three -phase measurement, and nature directly perceived is strong, and the measurement is accurate.

Description

Catamaran type oil well three-phase autmatic measuring device

Technical field

This utility model relates to a kind of for producing the Liquid output of oil well, gas production, well water crude oil mixed liquor density, oil well The water content of liquid and oil content carry out the equipment of automatic gauge, belong to oil well oil-gas water automatic Measurement Technology for Tri-phase field.

Background technology

The well stream thing of oil well production comprises Oil, Water, Gas and graininess solid, and the three-phase of Oil, Water, Gas accurately measures extremely difficult, Current three phase metering method is mass flowmenter method and liquid level method, all there is shortcoming in various degree.

Chinese patent literature CN103835697A is disclosed " individual well three-phase metering mechanism ", including once expanding pipe and quadratic extension Pipe, once expansion pipe connects with tapered cyclone separator, and once expansion pipe top connects with quadratic extension pipe；Quadratic extension pipe with Gas phase pipeline communication, gas phase pipeline by gas duplex rotor meter connect mixture export pipe, quadratic extension tube side part with once Expansion pipe connection, tapered cyclone separator is fixed on oil storage tank inner chamber top, connects with once expanding pipe；Outside at oil storage tank Upper and lower two liquid-level switches it are provided with on wall；In the bottom of oil storage tank, it is sequentially communicated pump, control valve, matter by liquid pipe Amount effusion meter and mixture export pipe；Two liquid-level switches, gas duplex rotor meter, mass flowmenter, control valve, pumps divide Do not connect controller by cable.CN101241121 is disclosed " timing method three phase metering separator ", only remembers in metering process Take three time parameters shown by three liquidometers, so that it may complete the metering of oil gas water three phase, and other is special without the most supporting Instrument.By the time measurement waiting height to mixed liquor liquidometer and corresponding water column liquidometer, synchronize to have sought out mixed liquor Weight (ton) and volume (just), and be derived densimetry and survey aqueous parameter ρ_Mixed=t₁/t₂*ρ_Water, thus calculate aqueous Rate；The zero-bit meter timing of drain chamber achieves the metering to gas production, it is achieved thereby that the chronometry of oil gas water three phase is asked for. CN103982170A is disclosed " low consumption of the liquid, atm number oil well three phase metering device in one ", mainly includes gas-liquid cyclonic separation Device, flow straightener, gas circuit surge tank, gas circuit metered flow meter, tipping bin flowmeter and differential pressure transmitter.Gas-liquid cyclone separator Major function has been the gas-liquid separation work that oil well carrys out liquid；The major function of flow straightener is to realize gas-liquid buffering current stabilization, separation oil Residual gas in water；The major function of gas circuit surge tank is to realize the profit in gas is carried out secondary separation；Gas circuit metered flow meter, The major function of tipping bin flowmeter is that gas circuit, fluid path medium are carried out flow real-time online metering.

Said apparatus or technical scheme, be required for using separator to carry out gas-liquid separation, and one is to use will produce with large-scale segregation apparatus Go out after thing is separated into single oil phase, aqueous phase, gas phase, measure oil phase, aqueous phase flow respectively with two groups of fluid flowmeters, with one Group gas phase flow rate meter metering gas phase flow rate.This kind of technical pattern is complicated, bulky, is not suitable for the individual well three-phase meter of on-the-spot oil well Amount application.Furthermore using mass flowmenter to carry out liquid measure exactly and hybrid density is measured, the method is unsuitable for the oil that gas production is bigger Well and heavy oil wells, three phase metering error is the biggest.

It addition, also there is the water, oil, gas three phase metering being carried out oil well by other technical approach:

CN102322908B is disclosed " differential pressure type oil-gas-water three-phase metering device ", including calorstat, gas-liquid separator, profit Separator and computer acquisition control processing system, described gas-liquid separator is connected with back-pressure valve, gas flowmeter and differential pressure and passes Sensor, oil water separator is connected with differential pressure pick-up, electromagnetic valve and balance, and gas-liquid separator is connected with oil water separator.This Utility model is that static oil-water-gas chemical examination is measured, it is impossible to apply on oil well automatic gauge.

CN103046919A disclosed " by liquid level and the method for differential pressure gauge amount output content from oil well ", is to go here and there in oil well output pipeline Connect a cylinder unit, in device, have stagnant sap cavity, measurement chamber, exhaust chamber, stagnant liquid valve, tapping valve, liquid level sensor, differential pressure Sensor and supporting control circuit, pressure transducer, temperature sensor etc.；During output content from oil well flows through cylinder unit, Need to be through the measurement chamber in device.Differential pressure pick-up, liquid level sensor carry out continual measurement to output content from oil well, obtain at any time Take the differential pressure of output content from oil well in measurement chamber, liquid level and supporting temperature, pressure and other parameters；Control circuit is by known conditions oil Density p oil, the density p water of water, floor space S of measurement chamber, the level parameter arrived in conjunction with liquid level sensor measurement and differential pressure Weight parameter under this liquid level that sensor measurement arrives, obtain the volume V of output content from oil well in measurement chamber survey, the volume V oil of oil, The volume V water of water, quality, the quality of water and the moisture content of oil.This utility model belongs to the metering of the interruption to oil well, it is impossible to Realize measuring continuously.Meanwhile, this technology cannot accurately record the liquid level of oil-water mixture, the most just cannot be carried out oil well three-phase metering.

CN201025024 disclosed " oil well pressure differentiation measurement device ", in tank body from top to bottom order be fixed with liquid level upper limit switch, Double flanges differential pressure transmitter and liquid level lower limit switch, the data acquisition controller aerofluxus exported, feed liquor, discharge opeing control signal As the control signal of corresponding electromagnetic valve, by high level limit switch, liquid level upper limit switch, double flanges differential pressure transmitter and liquid The signal of position limit switch output is separately input to the corresponding data collection terminal of data acquisition controller.This utility model uses liquid level Switch and the hybrid density of differential pressure transmitter conjunction measuring produced liquid in oil well, owing to liquid-level switch has mechanical clearance, liquid level is floated simultaneously Ball immersion in different oil densities crosses difference deeply, actually cannot Accurate Determining mixing liquid level, thus measure Resultant error is the biggest.

, at the scene in the application of oil well three-phase automatic on-line continuous metering, there is corresponding defect, apply effect in above-mentioned utility model Undesirable.

Summary of the invention

This utility model is for the deficiency of the Oil, Water, Gas three-phase on-line metering technology existence of existing oil well, it is provided that a kind of structure letter Single, can automatic on-line metering, metering precision is high, the suitability is strong, real-time catamaran type oil well three-phase autmatic measuring device.

Catamaran type oil well three-phase autmatic measuring device of the present utility model, employing following technical proposals:

This quantifier includes the first tank body, the second tank body；First electric T-shaped valve, the second electric T-shaped valve and automatic controller； Be provided with the first differential pressure transmitter and the 3rd differential pressure transmitter on first tank body, the second tank body is provided with the second differential pressure transmitter and 4th differential pressure transmitter；The upward pressure interface of the 3rd differential pressure transmitter and the 4th differential pressure transmitter is respectively lower than the first differential pressure transmitter Upward pressure interface with the second differential pressure transmitter；The downforce interface of the 3rd differential pressure transmitter and the 4th differential pressure transmitter is respectively higher than The downforce interface of the first differential pressure transmitter and the second differential pressure transmitter；The import of two tank bodies respectively with the first electric T-shaped valve Two output interfaces connect, and the outlet of two tank bodies is connected with two output interfaces of the second electric T-shaped valve respectively, two tank bodies Top connect have the communicating pipe for gas exchange；The top of tank body is equipped with pressure transmitter and a temperature transmitter (tank body Top another tank body equipped with pressure transmitter top dress temperature transmitter)；Four differential pressure transmitters, two electronic three Logical valve, pressure transmitter and temperature transmitter are all connected with automatic controller；

Controller controls two electric T-shaped valves, and making crude oil enter a tank body becomes feed liquor tank body, and another tank body is then discharged Crude oil becomes emptying tank body；Differential pressure value (the first differential pressure transmitter or the output valve of the second differential pressure transmitter) when feed liquor tank body After exceeding setting value, control two electric T-shaped valves and make the feed liquor of two tank bodies exchange with emptying state；Two tank bodies alternately enter Crude oil and emptying, two tank bodies are full symmetric and carry out gas exchange by communicating pipe；

The upward pressure interface position of the 3rd differential pressure transmitter and the 4th differential pressure transmitter is defined as density measure position；When liquid level surpasses After crossing density measure position, the differential pressure value of the first differential pressure transmitter or the second differential pressure transmitter continues to increase, the 3rd differential pressure transmitter Or the 4th the differential pressure value of differential pressure transmitter constant；According to the first differential pressure transmitter and the 3rd differential pressure transmitter differential pressure value change or It is the differential pressure value change of the second differential pressure transmitter and the 4th differential pressure transmitter, it is judged that whether liquid level is higher than density measure position；When When liquid level exceedes density measure position, connect according to the 3rd differential pressure transmitter or the upward pressure interface of the 4th differential pressure transmitter and downforce Height and the differential pressure value of mouth measure liquid-tight degree；

Differential pressure value according to the first differential pressure transmitter and the second differential pressure transmitter measures the liquid measure weight in two tank bodies respectively；Root The liquid measure volume in two tank bodies and gas compartment volume is measured according to liquid-tight degree；Change according to the liquid measure entering tank body and measure production fluid The weight and volume of amount；Change according to gas compartment volume measures the gas production under operating mode；According to the gas production under operating mode, Gas production under pressure and temperature data metering bid condition；The oil-water ratio of liquid is calculated according to liquid-tight degree, oil density and water density Example, and then measure weight of oil, oil volume, water weight and water volume；Realize oil well three-phase automatic continuous measuring.

The computing formula of described liquid-tight degree is:

$\mathrm{\ρ}=\frac{P3\×S}{h\×S}=\frac{P3}{h},$

Wherein: ρ is liquid-tight degree；P3 is by the 3rd differential pressure transmitter or the 4th differential pressure transporting when liquid level exceedes density measure position The output valve of device；H is the upper of upward pressure interface and the spacing of downforce interface of the 3rd differential pressure transmitter or the 4th differential pressure transmitter Pressure interface and the spacing of downforce interface；S is the sectional area of single tank body.

The computing formula of described Liquid output is:

M1=∑ Δ P1XS.

Wherein: M1 is Liquid output；P1 is differential pressure value (the first differential pressure transmitter or second differential pressure transmitter of feed liquor tank Output valve)；S is the sectional area of single tank body.

The volume of described Liquid output calculates according to Liquid output and liquid-tight degree:

$V1=\frac{M1}{\mathrm{\ρ}}.$

The volume computing formula of the gas production under described operating mode is:

$Q1=-\mathrm{\Σ}(\mathrm{\Δ}P1+\mathrm{\Δ}P2)\frac{S}{\mathrm{\ρ}},$

Wherein: P1: the differential pressure value of feed liquor tank；(the second differential pressure transmitter or the first differential pressure become the differential pressure value of P2: drain tank Send the output valve of device)；S: the sectional area of single tank body；ρ is liquid-tight degree.

Gas production computing formula under described mark condition is:

$Q2=\mathrm{\Σ}\mathrm{\Δ}\left(\right(V-\left(P1+P2\right)\×\frac{S}{\mathrm{\ρ}})\×\frac{(P+101.325)\×273.15}{101.325\×(T+273.15)}),$

Wherein: the cumulative volume of V: two tank bodies；P1: the differential pressure value of feed liquor separator；P2: the differential pressure value of emptying separator；S: The sectional area of single tank body；ρ is liquid-tight degree；T: the gas temperature read by temperature transmitter；P: read by pressure transmitter Gas pressure.

Described water weight computing formula:

$M3=M1\×Per=M1\×\frac{\mathrm{\ρ}2\×(\mathrm{\ρ}-\mathrm{\ρ}1)}{\mathrm{\ρ}\×(\mathrm{\ρ}2-\mathrm{\ρ}1)}$

Wherein: M1 is Liquid output；ρ is liquid-tight degree；ρ 1 is oil density；ρ 2 is water density.

Described water volume computing formula:

$V3=\frac{M3}{\mathrm{\ρ}2}$

Described weight of oil computing formula:

$M2=M1\×(1-Per)=M1\×\frac{\mathrm{\ρ}1\×(\mathrm{\ρ}2-\mathrm{\ρ})}{\mathrm{\ρ}\×(\mathrm{\ρ}2-\mathrm{\ρ}1)},$

Described oil volume computing formula:

$V2=\frac{M2}{\mathrm{\ρ}1}.$

This utility model alternately enters mixed liquor and the emptying of oil well output by two tank bodies, it is not necessary to other measurement instrument external, Simple in construction, only can measure oil-water ratio (oil mass and the water yield) and gas production by the data splitting of four differential pressure transmitters. First differential pressure transmitter and the second differential pressure transmitter for directly measuring Liquid output, when in tank body liquid level more than the 3rd differential pressure transmitter Or metering mixed liquor density during the 4th upward pressure interface of differential pressure transmitter；Under 3rd differential pressure transmitter and the 4th differential pressure transmitter When pressure interface is respectively lower than the downforce interface of the first differential pressure transmitter and the second differential pressure transmitter, differential pressure transmitter can be eliminated The impact that fluid density is measured by null offset.Achieving oil well flow and carry out the real-time automatic gauge of on-line continuous, intuitive is strong, Accurate measurement.

Accompanying drawing explanation

Fig. 1 is the structural representation of this utility model catamaran type oil well three-phase autmatic measuring device.

Wherein: 1, the first tank body；2, the second tank body；3, the first differential pressure transmitter；4, the second differential pressure transmitter；5, Three differential pressure transmitters；6, the 4th differential pressure transmitter；7, the first electric T-shaped valve；8, the second electric T-shaped valve；9, pressure becomes Send device；10, temperature transmitter；11, PLC；12, communicating pipe；13, base；14, sewage draining exit.

Detailed description of the invention

As it is shown in figure 1, catamaran type oil well three-phase autmatic measuring device of the present utility model, mainly include first tank body the 1, second tank Body 2 and PLC 11, the first tank body 1 and the second tank body 2 are arranged on base 13 side by side.First tank body 1 and second The import of tank body 2 connects two output interfaces of the first electric T-shaped valve 7 respectively, and the outlet of two tank bodies is electronic with second respectively Two output interfaces of three-way valve 8 connect.The input interface of the first electric T-shaped valve 7 is as oil well crude oil import, and second is electronic The input interface of three-way valve 8 exports as oil well crude oil.First electric T-shaped valve 7 and the input interface of the second electric T-shaped valve 8 Can only connect with one output interface.The top of two tank bodies connects the communicating pipe 12 for gas exchange.First tank body 1 Top pressure transmitter 9 is installed, the top of the second tank body 2 is provided with temperature transmitter 10, is used for measuring tank body top gas Body pressure and temperature.The first differential pressure transmitter 3 and the 3rd differential pressure transmitter 5, the 3rd differential pressure it is provided with on first tank body 1 The upward pressure interface of transmitter 5 is less than the upward pressure interface of the first differential pressure transmitter 3, and the downforce of the 3rd differential pressure transmitter 5 connects Mouth is higher than the downforce interface of the first differential pressure transmitter 3.The second differential pressure transmitter 4 and the 4th differential pressure it is provided with on second tank body 2 Transmitter 6, the upward pressure interface of the 4th differential pressure transmitter 6 is less than the upward pressure interface of the second differential pressure transmitter 4, the 4th differential pressure The downforce interface of transmitter 6 is higher than the downforce interface of the second differential pressure transmitter 4.First tank body 1 and the end of the second tank body 2 Portion is provided with sewage draining exit 14.Four differential pressure transmitters, two electric T-shaped valves, pressure transmitter and temperature transmitter all with PLC 11 connects.

The input interface of oil well crude oil input pipe and the first electric T-shaped valve 7 is connected, crude oil outlet tube and the second electric T-shaped valve The input interface of 8 connects.PLC 11 controls the first electric T-shaped valve 7 and switch direction of the second electric T-shaped valve 8. If controlling the input port of the first electric T-shaped valve 7 and the inlet communication of the first tank body 1, the import with the second tank body 2 ends (no Connection), the outlet cut-off of the input port of the second electric T-shaped valve 8 and the first tank body 1 and with the outlet of the second tank body 2, Now crude oil enters the first tank body 1, and the crude oil liquid level in the first tank body 1 rises, and the gas in the first tank body 1 passes through communicating pipe 12 enter the second tank body 2, the second tank body 2 automatic-discharging.First tank body 1 becomes feed liquor tank body, and the second tank body 2 then becomes row Slack tank body.After the differential pressure value (output valve of the first differential pressure transmitter 3) in the first tank body 1 exceedes setting value, PLC controls Device 11 controls the switch counteragent of two electric T-shaped valves, makes the feed liquor of two tank bodies exchange with emptying state.Two tank bodies Alternately crude oil and emptying, two tank bodies carry out gas exchange by communicating pipe.

The upward pressure interface position of the 3rd differential pressure transmitter 5 and the 4th differential pressure transmitter 6 is defined as density measure position.To enter As a example by flow container body is the first tank body 1, when liquid level is less than density measure position, the first differential pressure transmitter 3 and the 3rd differential pressure become The output valve (differential pressure value) sending device 5 rises along with liquid level and synchronizes to increase, and liquid level exceedes the first differential pressure transmitter 3 behind this position Output valve continues to increase, and the output valve of the 3rd differential pressure transmitter 5 is constant.According to the first differential pressure transmitter 3 and the 3rd differential pressure transporting The output valve change of device 5 can determine whether out that whether liquid level is higher than density measure position.When liquid level exceedes density measure position, according to The upward pressure interface of the 3rd differential pressure transmitter 5 and the height of downforce interface and differential pressure value measure liquid-tight degree.

Output valve according to the first differential pressure transmitter 3 and the second differential pressure transmitter 4 can measure the liquid measure weight in two tank bodies respectively Amount.The liquid measure volume in two tank bodies and gas compartment volume is measured according to liquid-tight degree.Liquid measure change according to feed liquor tank body can Measure the weight and volume of Liquid output.Change according to gas compartment volume measures the gas production under operating mode；According under operating mode Gas production, gas production under pressure and temperature data measurable bid condition.

The oil-water ratio of liquid can be calculated according to mixed liquor density, oil density and water density, and then measure oil mass and the water yield； Realize oil well three-phase automatic continuous measuring.

First differential pressure transmitter 3 and the second differential pressure transmitter 4 are for directly measuring Liquid output, when in tank body, liquid level is poor more than the 3rd Metering mixed liquor density during the upward pressure interface of pressure transmitter 5 or the 4th differential pressure transmitter 6.3rd differential pressure transmitter 5 and the 4th When the downforce interface of differential pressure transmitter 6 is respectively lower than the downforce interface of the first differential pressure transmitter 3 and the second differential pressure transmitter 4, The impact that fluid density is measured by differential pressure transmitter null offset can be eliminated.

The measurable oil-water ratio of combination, oil mass, the water yield and the gas production of four differential pressure transmitters.By the first differential pressure transmitter 3, Second differential pressure transmitter the 4, the 3rd differential pressure transmitter the 5, the 4th differential pressure transmitter 6, pressure transmitter 9 and temperature transmitter 10 Can directly read data below:

The differential pressure value (first differential pressure transmitter 3 or the output valve of the second differential pressure transmitter 4) of P1: feed liquor tank body.

P2: the differential pressure value (second differential pressure transmitter 4 or the output valve of the first differential pressure transmitter 3) of emptying tank body.

P3: the differential pressure value (being used for measuring density) read by the 3rd differential pressure transmitter 5.

P4: the differential pressure value (being used for measuring density) read by the 4th differential pressure transmitter 6.

T: the gas temperature exported by temperature transmitter 10.

P: the gas pressure exported by pressure transmitter 9.

According to data above, data below can be calculated:

ρ: liquid-tight degree；

M1: Liquid output (unit of weight)；

M2: the oil mass (unit of weight) in Liquid output；

M3: the water yield (unit of weight) in Liquid output；

V1: Liquid output (volume unit)；

V2: the oil mass (volume unit) in Liquid output；

V3: the water yield (volume unit) in Liquid output；

Q1: gas production (operating mode)；

Q2: gas production (mark condition).

Need to use data below constant:

ρ 1: oil density；

ρ 2: water density；

The cumulative volume of V: two tank bodies；

The upward pressure interface of the h: the three differential pressure transmitter 5 and the spacing of downforce interface, or the upper pressure of the 4th differential pressure transmitter 6 Power interface and the spacing of downforce interface；

S: the sectional area of single tank body.

Liquid output given below, liquid-tight degree, gas production, oil mass and the computing formula of the water yield.

1. Liquid output computing formula

According to the definition of pressure, the liquid measure in feed liquor tank body is P1X S, and the liquid measure in drain tank body is P2XS, according to feed liquor tank The change metering Liquid output of internal liquid measure, computing formula is:

M1=∑ Δ P1XS.

2. liquid densitometry

Here as a example by the liquid-tight degree of survey of the 3rd pressure difference transmitter 5.

Between upward pressure interface and the downforce interface of the 3rd differential pressure transmitter 5, the volume of liquid measure is hXS, and weight is P3XS, that Liquid-tight degree is:

$\mathrm{\ρ}=\frac{P3\×S}{h\×S}=\frac{P3}{h}.$

According to liquid-tight degree, the volume of Liquid output can be calculated:

$V1=\frac{M1}{\mathrm{\ρ}}.$

3. gas production computing formula

According to the definition of pressure, the liquid measure in feed liquor tank body is P1X S, and the liquid measure in drain tank body is P2XS, is respectively divided by liquid Density, can calculate the liquid volume in two tank bodies, can calculate the gas production under operating mode according to the change of liquid volume:

$Q1=-\mathrm{\Σ}(\mathrm{\Δ}P1+\mathrm{\Δ}P2)\frac{S}{\mathrm{\ρ}}.$

First calculate gas compartment cumulative volume according to pressure and temperature, represent with Q3:

$Q3=V-(\frac{F1\×S}{\mathrm{\ρ}}+\frac{F2\×S}{\mathrm{\ρ}})=V-(P1+F2)\×\frac{S}{\mathrm{\ρ}},$

Calculate gas volume under bid condition again, represent with Q4:

$Q4=(V-(P1+P2)\×\frac{S}{\mathrm{\ρ}})\×\frac{(P+101.325)\×273.15}{10.325\×(T+273.15)},$

The gas production under variable quantity metering mark condition according to Q4:

$Q2=\mathrm{\Σ}\mathrm{\Δ}\left(\right(V-\left(P1+F2\right)\×\frac{S}{\mathrm{\ρ}})\×\frac{(P+101.325)\×273.15}{101.325\×(T+273.15)}).$

4. the oil mass in liquid measure and the water yield calculate

Moisture ratio (part by weight) can be calculated according to oil density and water density:

$Per=\frac{\mathrm{\ρ}2\×(\mathrm{\ρ}-\mathrm{\ρ}1)}{\mathrm{\ρ}\×(\mathrm{\ρ}2-\mathrm{\ρ}1)},$

And then calculate fuel-displaced and water weight and volume:

$M2=M1\×(1-Per)=M1\×\frac{\mathrm{\ρ}1\×(\mathrm{\ρ}2-\mathrm{\ρ})}{\mathrm{\ρ}\×(\mathrm{\ρ}2-\mathrm{\ρ}1)},$

$V2=\frac{M2}{\mathrm{\ρ}1},$

$M3=M1\×Per=M1\×\frac{\mathrm{\ρ}2\×(\mathrm{\ρ}-\mathrm{\ρ}1)}{\mathrm{\ρ}\×(\mathrm{\ρ}2-\mathrm{\ρ}1)},$

$V3=\frac{M3}{\mathrm{\ρ}2}.$

Claims (1)

1. a catamaran type oil well three-phase autmatic measuring device, including two identical first tank bodies of tank body size, the second tank bodies；First electric T-shaped valve, the second electric T-shaped valve and automatic controller；It is characterized in that: on the first tank body, be provided with the first differential pressure transmitter and the 3rd differential pressure transmitter, the second tank body is provided with the second differential pressure transmitter and the 4th differential pressure transmitter；The upward pressure interface of the 3rd differential pressure transmitter and the 4th differential pressure transmitter is respectively lower than the upward pressure interface of the first differential pressure transmitter and the second differential pressure transmitter；The downforce interface of the 3rd differential pressure transmitter and the 4th differential pressure transmitter is respectively higher than the downforce interface of the first differential pressure transmitter and the second differential pressure transmitter；The import of two tank bodies is connected with two output interfaces of the first electric T-shaped valve respectively, and the outlet of two tank bodies is connected with two output interfaces of the second electric T-shaped valve respectively, and the top of two tank bodies connects the communicating pipe for gas exchange；The top of tank body is equipped with pressure transmitter and temperature transmitter；Four differential pressure transmitters, two electric T-shaped valves, pressure transmitter and temperature transmitter are all connected with automatic controller.